Oil spill response system

ABSTRACT

In an oil spill response system, oil on the water surface is collected into an oil combating vessel having at its side an inlet at the water level and a water flow conduit extending from the inlet, the flow conduit having an oil separating unit separating the oil present on the surface, and the flow conduit leading to a return conduit provided with an outlet. The oil separating unit includes a first separator installed in the flow conduit in the flow direction of water and formed by a brush cassette constituting a separating surface obliquely rising from the water in the flow direction of water, and following the brush cassette a framework module disposed in the flow conduit, to which framework module the brush cassette is supported. The framework module has a second separator with a rotating drum brush, and water outlets directing the cleaned water to the return conduit.

FIELD OF THE INVENTION

The invention relates to an oil spill response system as defined in thepreamble of claim 1. Particularly, the invention relates to an oil spillresponse system suitable for treatment of petroleum and for its removalfrom the surface of water.

BACKGROUND OF THE INVENTION

Prior art in the field of the invention has been disclosed in patentFI68694. In the oil-spill-combatting water craft according to thepublication, the oil present on the water is directed, by means of awater flow, into a conduit disposed in the interior of the water craft,wherein the oil is separated from the surface of water by means of arotating brush cassette. The device functions well when the structure ofthe brush is appropriately adapted to the properties of the oil to becollected. The properties of petroleum change considerably as it floatson the surface of water. The change is influenced by time andtemperature. At first, petroleum released into water from the land, seabottom or a ship, is very light. In time, the light materials evaporatefrom the petroleum into air. Finally, the oil is emulsified with water,forming a gelatinous mass. Thus, the known oil collectors functionoptimally only for a specific type of oil; yet the purpose is always tobe able to collect out all available oil from the surface of water asquickly as possible. As the separator is located in the interior of theconduit, its service and cleaning is difficult, and quick readjustmentsto it according to the properties of the oil to be collected are notpossible.

OBJECTIVE OF THE INVENTION

The objective of the invention is to remedy the defects of the prior artreferred to above. Particularly, the objective of the invention is todisclose a novel oil spill response system, by means of which the oilcan be effectively recovered continuously, irrespective of the viscosityof the oil, which can be easily serviced and repaired and which is anassembly that is separate of the ship, enabling its quick installationand replacement according to changing collecting conditions.

SUMMARY OF THE INVENTION

The oil spill response system according to the invention is used forcollecting the oil present at the water surface into an oil combattingvessel having at the side thereof an inlet located at the water level,and a water flow conduit beginning at the inlet. The flow conduitincludes an oil separating unit for separating the oil present on thesurface of water. Finally, the cleaned water is directed into a returnconduit provided with an outlet. According to the invention, the oilseparating unit includes a first separator to be installed into the flowconduit in the flow direction of water and being formed by a brushcassette constituting a separating surface obliquely rising from thewater in the flow direction of water. Following the brush cassette, theflow conduit has a framework module, to which the brush cassette issupported and which has a second separator comprising a skimmer providedwith a rotating drum brush and a cleaning comb. Further, the frameworkmodule has water outlets for directing cleaned water to the returnconduit.

Thus, the oil separating unit according to the invention constitutes aseparate and detached assembly which has a framework module, a skimmerdisposed in the interior of the framework module and a brush cassettesupported onto the framework module. This assembly can be moved andinstalled in a flow conduit provided in a ship as a functional assemblywithout having to carry out actual installation work at the ship. In apreferred embodiment of the invention, the framework module includessuitable suspension or support members, by means of which it issupported to the front wall of a collector tank. Thus, the frameworkmodule with the separators can be accurately installed in an appropriateposition relative to the collector tank.

Preferably, the first belt-type separator extends sufficiently highabove the water surface and the collector tank for oil is included belowthe top end thereof, while the second separator is disposed below thefirst separator before the collector tank in the flow direction ofwater. Thus, the oil collected by both of the separators is collectedinto the same collector tank, which considerably saves space and makesthe entire apparatus a small one.

In one embodiment of the invention, the bottom end of the brush cassetteis located in the immediate vicinity of the inlet of the conduit. Thus,it constitutes an effective wave absorber before the second oilseparator. In this case, no other wave absorbing structures are neededfor the conduit; instead, it can be made as a simple and straightstructure effectively directing the flows.

Preferably, the outlet of the flow conduit, also suitably disposed atthe side of the vessel before the inlet in the direction of travel ofthe ship, includes flow guides arranged to constitute a negativepressure in the flow conduit for realizing a steady surface flow intothe inlet and to the area of the separators.

In the invention, the brush structure of the first separator isselected, as known per se, to be suitable for recovery of heavy oil aswell as debris and algae. The brush structure of the second separator isselected, as known per se, to be suitable for recovery of light oil.

The oil spill response system according to the invention providesconsiderable advantages as compared to the prior art. The idea accordingto the invention is based on the fact that no fixed oil separators needbe built on the ship; instead, the separators are located in a separateframework module that can be located as an assembly into a flow conduitprovided on the ship. Only a simple flow conduit need be made on theship. Secondly, the modules can be prefabricated to be suitable fordifferent types of oil pollution. Thus, deployment according to theconditions just by selecting the suitable framework module is veryquick. Further in the invention, oily debris and algae as well as heavyoil are first removed from the water, the light oil flowing through thefirst separator to the second separator, wherein it is collected. Thus,the oil collecting devices do not require any adjustment as theproperties of the oil change in the course of the collecting activity;instead, the apparatus continuously functions in an optimal fashion,recovering both heavy and light fractions of the oil. In the invention,the collection of the oil proceeds steadily and steplessly from onecollector to the other as the properties of the oil change.

LIST OF FIGURES

In the following section, the invention will be described in detail withreference to the accompanying drawings, in which

FIG. 1 illustrates the structure according to the invention as across-sectional side view,

FIG. 2 illustrates the structure of FIG. 1 as seen from the top,

FIG. 3 illustrates a flow conduit from the side,

FIG. 4 illustrates a flow conduit from the top,

FIG. 5 illustrates a second embodiment of a flow conduit from the side,

FIG. 6 illustrates the embodiment of FIG. 5 from the top, and

FIG. 7 illustrates a brush structure of a second separator.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1 and 2 show, at the side 9 of a vessel 8, at the water level,i.e. partially above and partially below the water surface, an openingand closing hatch 10 which constitutes an inlet 1 for a substantiallyhorizontal water flow conduit 3 extending to the interior of the vessel.The flow conduit returns back to the side of the vessel along a returnconduit 15, constituting an outlet 2, via which the water flows out fromthe conduit.

Located in the flow conduit 3 there is a substantially equally wideframework module 25, i.e. a rigid framework structure, in the interiorof which a second separator 5, i.e. a skimmer, is located, a firstseparator 4, i.e. a brush cassette, being supported onto the frameworkmodule in an oblique position. At the inner end of the framework modulethere is a support structure 27, such as a groove-type holder, by meansof which the framework module is suspended in its place at the edge ofan oil collector tank 6 disposed at the end of the conduit.

More precisely, the framework module 25 is so located in the flowconduit 3 that extending from below the water surface 11 right from thevicinity of the inlet 1 there is the first separator 4, i.e. a brushcassette, having a bottom end support roll 12, a top end support roll 13as well as a circulating belt 14 provided with a brush surface and ahousing. The brush cassette is oriented obliquely upward in the flowdirection of water in the flow conduit, and its top end rises so highabove the water surface 11 that the framework module 25 with the secondseparator 5, i.e. a skimmer, having a cylindrical brush, are disposed atan appropriate height partially below the water surface 1. Both theskimmer and the brush cassette have comb structures or scrapers 19,20known per se to clean their respective bristles. The brush cassette 4and the skimmer 5 are so located one above the other that impuritiesfrom both of them flow into the common collector tank 6. At the side ofthe framework module 25 there are water outlets 26, via which the watercleaned by the skimmer 5 is able to flow into the return conduit 15.

As seen from FIG. 2, the water returns along the return conduit 15 fromthe inner end of the flow conduit 3 to the outlet at the side of thevessel. In the outlet there are as flow guides a transverse hatch 16 aswell as a flow blocking wall 17 that is transverse in the direction ofmovement of the vessel so that the water is only let downward andbackward from the discharge conduit. As the vessel moves in thedirection of the arrow 18, this provides a steady suction into the flowconduit.

In accordance with FIG. 2, the framework module 25 has flow contractors21 reducing the width of the flow conduit 3 before the second separatorso that the flow of water is entirely caught on the brush surface of theskimmer. It is seen from the brush surface of FIG. 7 that at the edgesthereof there are (dotted) longer brushes 22 of approximately 50 mm andarrow type shapes 23 in the rotating direction from the respectivelonger bristles at the center, in which case between the edges and thearrow shapes there are left areas 24 of shorter bristles, wherein theoil is initially caught and wherefrom it is effectively absorbed intothe longer bristles.

From FIGS. 3 and 4 it is more specifically seen how water and impuritiespresent on the surface flow into the flow conduit 3 as directed by theopened hatch 10 and a long oil boom (not illustrated in the figure)attached to the hatch, and, after cleaning, from the flow conduit outfrom the vessel along the return conduit 15. The suction enhancing theflow is caused at the end of the return conduit 15 by the transversehatch 16 and the flow blocking wall 17 disposed at the front edge. It isto be noted that in this embodiment also the return conduit 15 isdisposed partially on the surface of water, i.e. the return conduit isonly partially filled with water. This is essentially important inrealizing a good suction at the end of the return conduit. To a straightand empty conduit 3 illustrated by FIGS. 3 and 4, the framework module25 according to the invention can be inserted to be fixed in its placeto be supported to the front edge of the collector tank 6 disposed atthe end of the conduit. It is clear that also other ways of attachmentare possible.

FIGS. 5 and 6 illustrate a second embodiment, wherein the return conduit15 is located below the flow conduit 3, i.e. entirely below the watersurface. Also in this embodiment, the return flow is directed steadilyto the area delimited by the hatch 10 and the oil boom, i.e. below theoil to be taken for cleaning. The appropriate and steady direction ofthe return flow prevents swirling of the oil present on the surface andits mixing with water before cleaning and simultaneously enables thesurfacing of impurities remaining in the return flow and their reflowinto the cleaning process.

The invention is not limited merely to the examples referred to above;instead, many variations are possible within the scope of the inventiveidea defined by the claims.

1. An oil spill response system for collecting the oil present on thewater surface into an oil combatting vessel which has at the sidethereof an inlet (1) located at the water level and a flow conduit (3)extending from the inlet, the flow conduit having an oil separating unitfor separating the oil present on the surface of water and the flowconduit leading to a return conduit (15) provided with an outlet (2),wherein the oil separating unit includes a first separator (4) to beinstalled in the flow conduit (3) in the flow direction of water andbeing formed by a brush cassette constituting a separating surfaceobliquely rising from the water in the flow direction of water, andfollowing the brush cassette a framework module (25) disposed in theflow conduit, to which framework module the brush cassette is supportedand which framework module has a second separator (5) provided with arotating drum brush, as well as water outlets (26) for directing thecleaned water to the return conduit (15).
 2. The oil spill responsesystem according to claim 1, wherein below the top end of the firstseparator (4) there is a collector tank (6), while the second separator(5) is disposed below the first separator before the collector tank inthe flow direction of water, in which case oil collected by both of theseparators is collected into the same collector tank.
 3. The oil spillresponse system according to claim 1, wherein the framework module (25)is supported to the front wall of the collector tank (6).
 4. The oilspill response system according to claim 1, wherein the bottom end ofthe brush cassette (4) is located in the immediate vicinity of the inlet(1) of the flow conduit (3) to form a wave absorber.
 5. The oil spillresponse system according to claim 1, wherein the outlet (2) of the flowconduit (1) includes flow guides (16,17) arranged to constitute anegative pressure in the flow conduit for realizing a steady surfaceflow to the inlet (1) and to the area of the separators (4,5).
 6. Theoil spill response system according to claim 1, wherein the brushstructure of the first separator (4) is selected to be suitable forrecovery of oil with a high viscosity as well as debris and algae. 7.The oil spill response system according to claim 1, wherein the brushstructure of the second separator (5) is selected to be suitable forrecovery of oil with a low viscosity.
 8. The oil spill response systemaccording to claim 2, wherein the framework module (25) is supported tothe front wall of the collector tank (6).
 9. The oil spill responsesystem according to claim 2, wherein the bottom end of the brushcassette (4) is located in the immediate vicinity of the inlet (1) ofthe flow conduit (3) to form a wave absorber.
 10. The oil spill responsesystem according to claim 3, wherein the bottom end of the brushcassette (4) is located in the immediate vicinity of the inlet (1) ofthe flow conduit (3) to form a wave absorber.
 11. The oil spill responsesystem according to claim 2, wherein the outlet (2) of the flow conduit(1) includes flow guides (16,17) arranged to constitute a negativepressure in the flow conduit for realizing a steady surface flow to theinlet (1) and to the area of the separators (4,5).
 12. The oil spillresponse system according to claim 3, wherein the outlet (2) of the flowconduit (1) includes flow guides (16,17) arranged to constitute anegative pressure in the flow conduit for realizing a steady surfaceflow to the inlet (1) and to the area of the separators (4,5).
 13. Theoil spill response system according to claim 4, wherein the outlet (2)of the flow conduit (1) includes flow guides (16,17) arranged toconstitute a negative pressure in the flow conduit for realizing asteady surface flow to the inlet (1) and to the area of the separators(4,5).
 14. The oil spill response system according to claim 2, whereinthe brush structure of the first separator (4) is selected to besuitable for recovery of oil with a high viscosity as well as debris andalgae.
 15. The oil spill response system according to claim 3, whereinthe brush structure of the first separator (4) is selected to besuitable for recovery of oil with a high viscosity as well as debris andalgae
 16. The oil spill response system according to claim 4, whereinthe brush structure of the first separator (4) is selected to besuitable for recovery of oil with a high viscosity as well as debris andalgae
 17. The oil spill response system according to claim 5, whereinthe brush structure of the first separator (4) is selected to besuitable for recovery of oil with a high viscosity as well as debris andalgae
 18. The oil spill response system according to claim 2, whereinthe brush structure of the second separator (5) is selected to besuitable for recovery of oil with a low viscosity.
 19. The oil spillresponse system according to claim 3, wherein the brush structure of thesecond separator (5) is selected to be suitable for recovery of oil witha low viscosity.
 20. The oil spill response system according to claim 4,wherein the brush structure of the second separator (5) is selected tobe suitable for recovery of oil with a low viscosity.